In applications, appliances, computer systems, or other systems where data and/or signals are scrambled, encrypted, or protected, there is often a control mechanism to allow the descrambling, decryption, or decoding of such data and/or signals. This control mechanism is often referred to as a conditional access (CA) system or module. The CA system may consist of several modules that perform functions. Some of the functions may be performed on a card which may be inserted into a system or slot. One common form factor is that of a smart card, another is Personal Computer Memory Card International Association (PCMCIA). Smart cards have several standards, one is International Organization for Standardization (ISO) 7816. Reference will be made to this specification as ISO 7816. PCMCIA cards have several standards, one is Type 2. Reference to a smart card is to be understood to refer to the ISO 7816 standard unless stated otherwise. Reference to a PCMCIA card is to be understood to refer to the PCMCIA Type 2 standard unless stated otherwise.
There are several standards for conditional access systems. In the U.S., one such standard is the National Renewable Security Standard (NRSS). The NRSS has defined two types of CA modules, a NRSS part A module (NRSS-A) with a smart card form factor, and NRSS Part B (NRSS-B) with a PCMCIA form factor. In the U.S., some other standards are OPENCABLE™ Host Point Of Deployment Interface Specification (POD), and Conditional Access System for Terrestrial Broadcast (ATSC-A70). In Europe, Digital Video Broadcasting (DVB) organization has defined a CA module similar to NRSS Part B called “Common Interface” (CI). For convenience, we shall refer to any CA protocols with smart card form factors (e.g., NRSS-A) as a “first” CA protocol and refer to CA protocols with PCMCIA form factors (e.g., NRSS-B) as a “second” CA protocol.
One of the challenges facing manufacturers building devices that have conditional access capability is that they want a standardized method for communicating to CA modules. NRSS Part A, which uses the smart card form factor, has technical implementation issues. NRSS part B modules, which are PCMCIA form factor, are expensive, and have some technical issues as well. Devices that may accept a CA module include, but are not limited to, televisions (TVs), video cassette recorders (VCRs), personal video recorders (PVRs), home jukebox players, set top boxes (STB) for terrestrial broadcast, cable, or satellite, etc. Manufacturers want the CA interface standardized so that the devices can be built in a generic way. The NRSS-A CA card is not a typical ISO 7816 smart card, and NRSS-A cards are not readily available.
A device (set top box, TV, VCR, etc.), which has both a CA interface for an ISO 7816 smart card, and a POD module typically has two separate interface protocols. Different CA protocols for different types of CA modules adds to the complexity of the device.